electromagnets

Up on the second level of World Maker Faire’s main hall, one could hear Technotronic’s hit “Pump up the Jam” playing again and again. We were expecting breakdancing robots, but upon investigating, what we found was something even better. [David Durlach] was showing off his Choreographed Iron Dust, a 9 x 9 grid of magnets covered in iron filings. The filings swayed and danced to the beat of the music, at times appearing more like ferrofluid than a dry material. Two LED lights shined on the filings from an oblique angle. This added even more drama to the effect as the light played on the dancing spikes and ridges.

While chatting with [David] he told us that this wasn’t a new hack. Choreographed Iron Dust made its debut at the Boston Museum of Science back in 1989. Suddenly the 80’s music made more sense! The dust’s basic control system hasn’t changed very much since the 1980’s. The magnets are actually a stack of permanent and electromagnets. The permanent magnet provides enough force to hold the filings in place. The electromagnets are switched on to make the filings actually dance.

Since it was designed in 1989, there were no Arduinos available. This project is powered by the most hacker friendly interface of the era: the PC’s parallel port. As one might imagine, [David] has been having a hard time finding PC’s equipped with parallel ports these last few years.

[David] wasn’t just showing off iron dust. Having spent so much time painstakingly animating the iron filings for various customers, he knew there had to be a better way. He’s come up with ChoreoV, a system which can take recorded video, live performances, or even capture a section of a user’s screen. The captured data can then be translated directly into light or motion on an art piece.

It’s not that touchscreen keyboards are horrible, but it’s nearly impossible to touch type on an iPad or other tablet keyboard. A team at the Media Computing Group at Aachen University figured out how to put a series of electromagnets underneath a display to provide haptic feedback for touchscreens. They showed off their tech at the 2011 UIST conference and made their paper available.

For the FingerFlux, as the team likes to call it, a bed of tiny electromagnets is placed underneath a panel display. The user wears a ‘thimble’ with an attached permanent magnet. Driving the bed of electromagnets slightly moves the magnet and provides a little bit of sensation to the user.

The FingerFlux can be used to provide haptic feedback like a keyboard. The system can also be used to model constraints – making sure that users don’t move outside the controls they operate, and can guide the user to the desired button.

A bed of electromagnets would be a welcome addition to tablets, if only to prevent typung luje rhus. Check out the demo of the FingerFlux after the break.